Naturally occurring variation in high temperature induced floral bud abortion across Arabidopsis thaliana accessions

Abstract

A system to study the basis of high temperature-induced floral bud abortion using naturally occurring variation for heat-tolerance of floral development among Arabidopsis thaliana (L.) Heynh. wild-collected accessions is described. High temperature-induced floral bud abortion was dependent on both temperature and duration of exposure. Exposing the inflorescence alone to high temperature was sufficient to induce floral bud abortion, and Col-0 and No-0 photosynthetic rates were similar during high temperature exposure and recovery, indicating that high temperature induced floral abortion is not simply due to reductions in carbon assimilation under high temperatures. Determining that exposing floral buds alone to high temperature is sufficient to induce abortion and identifying the stages of floral development sensitive to high temperature-induced abortion will aid in identifying the developmental events subject to disruption under high temperatures.

Genome-Wide Association Mapping of Fertility Reduction upon Heat Stress Reveals Developmental Stage-Specific QTLs in Arabidopsis thaliana

“…Reduced anther elongation upon heat stress has also been found in other species, such as barley (Sakata et al, 2010). The observations of Kim et al (2001) and Warner and Erwin (2005) are in line with our observation that natural variation exists both in terms of duration of the sensitivity window and the degree of reduction in seed set within the sensitivity window. However, comparison of floral stages between different studies should be done carefully since the matching between the developmental regions and the landmark events in flower and seed development are based on generalization and natural variation was observed for the number of flowers that opened per day.…”

“…In addition, a sensitive period at floral stage 12 was identified (Kim et al, 2001). A more extensive study in Arabidopsis, investigating floral bud abortion upon heat stress in 13 natural accessions, demonstrated that in the Columbia accession floral stage 12, but not floral stage 9, was most sensitive (Warner and Erwin, 2005). That floral stage 9 was not identified could be caused by the longer period of heat that was applied (36°C for 72 h).…”

“…Although a few studies have reported on the developmental sensitivity window upon heat stress (Kim et al, 2001;Warner and Erwin, 2005), this study is unique as it investigates this sensitivity window using a large natural population. Therefore, the data could be subjected to GWA mapping, which allowed the identification of stage-specific QTLs.…”

“…Also, a study in Arabidopsis reported natural variation for heat response during flowering (Warner and Erwin, 2005). Unfortunately, much less is known about the genetic factors that cause this variation in heat response.…”

“…Surprisingly, however, many studies in this species focus on the impact of elevated temperatures on germination (Baskin and Baskin, 1983;Schmuths et al, 2006;He et al, 2014;Silva-Correia et al, 2014), flowering time (Balasubramanian et al, 2006;Y. Li et al, 2014), and plant architecture (Wahid et al, 2007;Patel and Franklin, 2009;Antoun and Ouellet, 2013), but only very few address the impact of heat on fertility (Kim et al, 2001; (Warner and Erwin, 2005;Zinn et al, 2010).…”